Prime Minister John Howard had recklessly outed the role of one of Australia's spy agencies in relation to Iraq, Opposition Leader Mark Latham said today.

Mr Latham continued his attack on Mr Howard on Iraq after yesterday marked the most aggressive day in more than a week of accusation trading between Labor and the government.

"It was a very reckless piece of politics by John Howard in publicly outing the role of one of our spy agencies in relation to Iraq," he told ABC radio.

"That can only increase the level of risk for Australians in Iraq, both military and civilian, and it's a major concern.

"This is a reckless piece of politics that ultimately is at the expense of our capacity to successfully engage in the war against terror."

Mr Howard yesterday tabled a letter from Ron Bonighton, head of the top secret Defence Signals Directorate, confirming that Mr Latham had received a basic briefing on DSD's operations on January 5 this year but with no focus on Iraq.

He accused Mr Latham of fabricating the idea he had received briefings on Iraq.

But Mr Latham said he and Mr Bonighton had discussed Iraq.

"Mr Bonighton gave me a briefing on the role of defence intelligence in backing the ADF in Iraq and then we turned to the subject of weapons of mass destruction," he said.

He denied he had chosen to out the spy agencies, DSD and ASIS.

"I was not wanting to name ASIS. The prime minister did that, in saying I'd received a briefing from ASIS."

For his own part, Mr Latham said he had been forced to discuss the agencies to defend himself.

"I've been forced to defend myself," he said.

"It's been difficult because I've got to give myself a public defence. That's reasonable.

"But I've got to be careful in ensuring that what was the basic confidentiality of those briefings is still respected."